J/A+A/585/A84ivo://CDS.VizieR/J/A+A/585/A84doi:10.26093/cds/vizier.35850084CDSBiernaux J.Magain P.Sluse D.Chantry V.2015-12-23T06:53:51Z2015-12-23T07:44:37ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frgravitational-lensinggalaxiesvisible-astronomygalaxy-classification-systemsThe luminosity profiles of galaxies acting as strong gravitational lenses can be tricky to study. Indeed, strong gravitational lensing images display several lensed components, both point-like and diffuse, around the lensing galaxy. Those objects limit the study of the galaxy luminosity to its inner parts. Therefore, the usual fitting methods perform rather badly on such images. Previous studies of strong lenses luminosity profiles using software such as like GALFIT or IMFITFITS and various PSF-determining methods have resulted in somewhat discrepant results. The present work aims at investigating the causes of those discrepancies, as well as at designing more robust techniques for studying the morphology of early-type lensing galaxies with the ability to subtract a lensed signal from their luminosity profiles. The morphology of early-type lensing galaxies with the ability to subtract a lensed signal from their luminosity profiles. Methods. We design a new method to independently measure each shape parameter, namely, the position angle, ellipticity, and half- light radius of the galaxy. Our half-light radius measurement method is based on an innovative scheme for computing isophotes that is well suited to measuring the morphological properties of gravitational lensing galaxies. Its robustness regarding various specific aspects of gravitational lensing image processing is analysed and tested against GALFIT. It is then applied to a sample of systems from the CASTLES database.2016A&A...585A..84Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/585/A84CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/585/A84https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/585/A84http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/585/A84https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/585/A84https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/585/A84http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/585/A84GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/585/A84/table1 (List of the systems that have been processed in this work)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/585/A84/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/585/A84/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/585/A84/table1?GETtext/xml+votable180.050000true63.65720835.57897220.0055555555555555566/4124 8912 22581 23339 27004 27127 27318https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/585/A84?format=asciiOpticaldefaultJ/A+A/585/A84/table1List of the systems that have been processed in this workrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName of the systemmeta.id;pos.framecharNframesNumber of framesmeta.numberintSzSource redshiftsrc.redshift;pos.heliocentricfloatLzLens redshiftsrc.redshift;pos.heliocentricfloatRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainSNameSimbad namemeta.idcharJ/A+A/585/A84/table6Characteristics of the masks usedrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName of the systemmeta.id;pos.framecharxposx-coordinate of the galaxy center (xG - xA)pixpos.cartesian.x;instr.detdoubleyposy-coordinate of the galaxy center (xG - xA)pixpos.cartesian.y;instr.detdoublebmaxSemi-minor axis of the region of interest (1)pixphys.angSize.sminAxis;obs.fieldintFrameData frame name in the HST-NICMOS conventionobs.fieldcharPA1[] Mask position angle (in data frame reference)degpos.posAngdoublePA2[] Mask position angle (North Up, East Right)degpos.posAngdoubleellMask ellipticity (2)src.ellipticityfloatreffPSF-affected half-light radius of the galaxyarcsecphys.angSize;srcdouble